On most battery cross reference charts, the battery brand names are located in the top horizontal row. The battery models are listed vertically beneath each brand name. Find your battery brand name; next, look down the vertical column beneath it until you locate your battery model. The other models in your battery model's horizontal row are compatible with your battery.
There are battery cross reference charts for all types of batteries, including watch batteries, standard batteries and automotive batteries. Batteries.com, BatteriesInAFlash.com and WatchBatteryCrossReference.com offer online reference charts. Batteries.com provides a search function with which you can choose your device and battery brand to find compatible batteries. A reference chart and links to purchase replacement batteries are available on BatteriesInAFlash.com.
BatteriesAndButter.com offers a variety of reference charts for different kinds of battery. The standard battery chart lists information on industry standard batteries, such as A and AA. It provides details about the batteries' appearance and voltage and lists other industry names for standard batteries. The cordless phone battery chart lists Panasonic battery models alongside battery types, while the hearing aid battery chart compares Energizer and Panasonic batteries by size, model and color code.
WatchBattery.co.uk gives the option of sorting batteries by diameter or height. The site notes that you cannot substitute lithium watch batteries for 1.5-volt silver oxide watch batteries or alkaline watch batteries because the voltage differs. Use silver oxide batteries in place of mercury ones, which are no longer manufactured. WatchBattery.co.uk's reference chart contains links to further information about batteries and to a page where you can purchase replacement batteries.